I just ran across this on the guitar parts resource website and was wondering if anyone had heard of it. External Battery Systems For Active Electronics Eliminate the need for internal batteries with active guitar and bass pickups and electronics ! The X-Bat9TM & X-Bat18TM external battery systems eliminate the need for internal batteries required to power active pickups and electronics including models from EMG®, Seymour Duncan®, Bartolini® and others. With the X-BatTM system, the 9-Volt battery (X-Bat9TM) or batteries (X-Bat18TM) are located in the battery pack (shown above). The pickups and electronics in the instrument are powered using a stereo (2 wire plus shield) instrument cable to connect to the pack. It's like having a 9-Volt or 18 Volt "phantom power" supply for your active instrument! Ideal for Strats®, Teles®, Jazz Bass®, P-Bass® and other guitars and basses that require routing for batteries or require pickguard removal or other disassembly to change the batteries. Also great for mandolins, bouzoukis, violins and other instruments that are difficult to mount batteries internally. Click here to visit the website Seems like a neat product -- anyone familiar with it?